(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Alexander von Humboldt"

126                               LIFE   OF
created a picture of the entire earth and its laws from
the results of his comparisons- He has everywhere
interspersed numerous geognostic observations and
notes on the general formation of the soil between the
Altai and the Himalaya mountains, and his commu-
nications on the remarkable occurrence of volcanoes
in the middle of the continent, and far from the ocean,
are of great interest. Here Humboldt placed science
on a new footing, for he had had the special oppor-
tunity of observing the volcanoes in three different
quarters of the world. He perceived that the volcanic
phenomena could no longer be considered as belong-
ing to geological developments, but that they imist be
explained by physical history in general, as the vol-
canic activity seemed to him to be the result of a con-
tinual communication between the interior of the
earth, which is in a molten fluid condition, and the
atmosphere which surrounds the hardened and oxy-
dised crust of our planet. On this theory he explained
the still active and the extinct craters, the direction
of the mountain-ridges, and the formations of the soil;
he deciphered the traces of former terrestrial revolu-
tions, their relative age, and the physical powers which
have influenced and still influence the form of the
earth's surface. Thus the masses of lava which pour
from the craters were to him. the petrified streams of
formerly gushing springs of the interior of the earth ;
from, the connexion an<J similarity of effects he traced
the causes, and conditions of the formation of rocks
and superincumbent strata, of the chemical results of
volcanic eruptions, of elevations and depressions of the
earth's surface. By the strictest investigation of all
occurring new appearances, and by penetrating com-
bination of analogous, observed facts, he explained
numerous physical and geological problems,, whose
exact solution had hitherto been deemed impossible*
Humboldt thinks that the volcanic activity of our
earth, compared to former ages, is considerably de-
creased ; ^it can no longer bring forth new elevations
or heat in the north, but can only produce small